Not long after George Allen lost his U.S. Senate seat in Virginia in 2006, the Republican launched a private consulting business that bills itself as a “recognized leader in helping clients navigate the waters inside — and outside — the Beltway.”

Unlike many former lawmakers, Mr. Allen never registered as a lobbyist. An aide said he never wanted to be a lobbyist or run a lobbying firm. Still, Mr. Allen’s firm, George Allen Strategies, does list on its website as a “principal” the federal lobbyist and former Allen aide Paul Unger.

Despitelobbying Mr. Allen’s former colleagues in the Senate on behalf of George Allen Strategies in recent years, the former senator’s consulting business isn’t registered with Congress as a lobbying firm.

That’s because, even with Mr. Unger listed as a principal of George Allen Strategies, he is a contractor, not a part owner or employee. But if Mr. Unger were on the payroll and doing the same work, Mr. Allen’s firm would have to register as a lobbying firm — something political opponents likely would be quick to seize upon as Mr. Allen tries to reclaim his Senate seat, analysts say.

“That almost certainly would come up in a campaign,” said Dave Levinthal, a spokesman for the nonpartisan Center for Responsive Politics. “The term lobbying, whether fair or not, has certain connotations in people’s minds.

“There are plenty of people in the political-influence industry who do all they can to keep from having a big old scarlet letter L sewn into their suit, particularly if they have elected ambitions or if they just don’t want to be labeled as a lobbyist,” he said.

Campaign finance and ethics analysts say it’s legal for consulting firms to hire outside lobbyists, but they note that the arrangement at George Allen Strategies highlights the murkiness of federal lobbying registration rules.

“The Allen-Unger relationship appears to stretch evasion of the lobbying disclosure law to new heights,” said Craig Holman, legislative representative of the watchdog group Public Citizen. “George Allen Strategies cannot credibly hire one of its principals as an outside lobbyist and thereby avoid registration and disclosure requirements.

“I find the effort to do so truly stunning and should be immediately subject to legal scrutiny,” he said.

“Several years ago, I established my own lobbying firm which allows me to represent several clients and at times work with other firms like George Allen Strategies,” Mr. Unger wrote in an email to The Washington Times in response to inquiries about his lobbying work for Mr. Allen’s firm.

“As George Allen’s former legislative director, he was familiar with my understanding of relevant issues,” Mr. Unger wrote. “His firm, George Allen Strategies, offers clients strategic counsel and guidance but not lobbying. If the opportunity arose and their clients needed my expertise, George Allen Strategies might hire me on as an independent contractor to handle that aspect of the project. It was a good fit for me and my firm.”

The George Allen Strategies website does not state that it offers lobbying services, but it does make mention of Mr. Unger’s work as a lobbyist. In addition to listing Mr. Unger as a principal, it details how the firm’s strategic partnerships can help prospective clients.

The firm, based in the Old Town section of Alexandria, says that from 2007 to 2009, Mr. Unger was vice president of federal public affairs at McGuireWoods Consulting, where he “where he lobbied for a variety of business clients.”

Fred Wertheimer, president of the District-based Democracy 21, a campaign finance watchdog group, called the outsourcing arrangement “rather confusing” considering that Mr. Unger is listed as a principal of George Allen Strategies.

“It’s not the way you’d normally describe the word principal, as an independent contractor,” he said. “It looks like the firm is attempting to offer lobbying services for their clients without having to be treated as a lobbying firm.”

Melanie Sloan, executive director of the District-based Citizens for Responsibility and Ethics in Washington, said it’s not unusual for consulting firms to hire outside lobbyists.

“But usually there’s more of an arm’s-length relationship,” she said. “Here, it sounds like George Allen doesn’t want anyone accusing him of being a lobbyist.”